Highly oxygenated sesquiterpenes from Polyachyrus sphaerocephalus and further constituents from chilean mutisieae

Abstract

The aerial parts of Polyachyrus sphaerocephalus gave seven new eudesmane derivatives and a germacra-dien-diol while a reinvestigation of P. fuscus afforded a new caryophyllene, two nerolidolglycosides, a curcumene and two bisabolene derivatives. Chaetanthera euphrasioides gave a clerodane and Ch. chilensis two thiophene acetylenes while several other species only gave known compounds. The structures were elucidated by high field NMR techniques. Chemotaxonomic aspects are discussed briefly. © 1992.